package com.kaola.gulimall.product.service.impl;

import com.kaola.gulimall.product.service.CategoryBrandRelationService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.kaola.common.utils.PageUtils;
import com.kaola.common.utils.Query;

import com.kaola.gulimall.product.dao.CategoryDao;
import com.kaola.gulimall.product.entity.CategoryEntity;
import com.kaola.gulimall.product.service.CategoryService;
import org.springframework.transaction.annotation.Transactional;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Autowired
    CategoryBrandRelationService categoryBrandRelationService;
    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1. 查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);

        //2. 组装树形结构
        // 2.1 找到所有一级分类 （父分类id为0）
        List<CategoryEntity> level1Menu = entities.stream().filter(categoryEntity->
             categoryEntity.getParentCid() == 0
        ).map((menu)->{
            menu.setChildren(getChildrens(menu, entities));
            return menu;
        }).sorted((menu1, menu2)->{
            return (menu1.getSort() == null?0:menu1.getSort()) - (menu2.getSort() == null?0:menu2.getSort());
        }).collect(Collectors.toList());
        return level1Menu;
    }

    @Override
    public void removeMenuByIds(List<Long> asList) {
        //TODO 删除之前需要判断待删除的菜单那是否被别的地方所引用.

        //
        baseMapper.deleteBatchIds(asList);
    }

    @Override
    public Long[] findCatelogPath(Long catelogId) {

        List<Long> paths = new ArrayList<>();
        paths = findParentPath(catelogId, paths);
        // 收集的时候是顺序 前端是逆序显示的 所以用集合工具类给它逆序一下
        Collections.reverse(paths);
        return paths.toArray(new Long[paths.size()]);
    }

    /**
     * 级联更新所有更新的数据
     */
    @Transactional
    @Override
    public void updateCascade(CategoryEntity category) {
        this.updateById(category);
        categoryBrandRelationService.updateCategor(category.getCatId(), category.getName());
    }

    /**
     * 递归收集所有父节点
     */
    private List<Long> findParentPath(Long catlogId, List<Long> paths) {
        // 1、收集当前节点id
        paths.add(catlogId);
        CategoryEntity byId = this.getById(catlogId);
        if (byId.getParentCid() != 0) {
            findParentPath(byId.getParentCid(), paths);
        }
        return paths;
    }

    /**
     * @Author zhang-hairong
     * @Description //递归查找找到所有 子菜单
     * @Date 12:58 2021/10/25
     * @Param [root, all]
     * @return java.util.List<com.kaola.gulimall.product.entity.CategoryEntity>
     **/
    private List<CategoryEntity> getChildrens(CategoryEntity root, List<CategoryEntity> all) {
        List<CategoryEntity> children = all.stream().filter(categoryEntity -> {
            // 父id == root 的ID
            return categoryEntity.getParentCid() == root.getCatId();
        }).map(categoryEntity -> {
            // 1. 找到子菜单
            categoryEntity.setChildren(getChildrens(categoryEntity, all));
            return categoryEntity;
        }).sorted((menu1, menu2) -> {
            // 2. 排序
            return (menu1.getSort() == null?0:menu1.getSort()) - (menu2.getSort() == null?0:menu2.getSort()) ;
        }).collect(Collectors.toList());

        return children;
    }
}